Closing words: Diabetes in Canada: Facts and figures from a public health perspective

Closing words

The number of Canadians with diabetes is growing at an alarming rate. In 2008/09, one in every 15 Canadians was living with diabetes. In addition, according to recent Canadian data, there may be up to 20% of individuals with diabetes whose disease has not yet been diagnosed. From 1998/99 to 2008/09, the age-standardized prevalence of diagnosed diabetes increased by 70%. Although the incidence rate has only slightly increased during the same period, the highest relative increase of newly diagnosed cases was seen in the 30 to 44 year age group. If the current incidence and mortality trends continue, it is estimated that there will be 3.8 million Canadians with diabetes in 2018/19.

There were 200,000 Canadians newly diagnosed with diabetes in 2008/09, with nearly half between the ages of 45 to 64 years old. Obesity is a major contributor to the development of diabetes in this age group, with nearly half (47.5%) of those with diabetes reporting obesity, compared to only 19.1% among those without diabetes. Since increasing age is also a major factor for type 2 diabetes, the aging of the "baby boom" cohort has begun and will continue to have an impact on the incidence and prevalence of diabetes in Canada.

The incidence of diabetes has not increased sufficiently over the last decade to account for the distinct rise observed in prevalence, which is a clear indication that the increase in prevalence is mainly due to the longer duration of the disease among those diagnosed with diabetes. While this is likely due to improved care and treatment, it may also indicate earlier detection of those with undiagnosed diabetes or earlier age of onset of diabetes. However, the implication of this is that the longer an individual lives with diabetes, the higher the risk of developing long term debilitating complications, such as end-stage renal disease, vision loss, or lower limb amputation. Moreover, the impact of diabetes extends beyond those living with the disease and their family; it also has a major impact on the Canadian health care system. The economic costs associated with treating and managing diabetes are expected to increase greatly in the coming years as a result of both the increased prevalence of diabetes and the ongoing rise in health care costs.

Although some aspects of the current situation may appear gloomy, scaling up prevention can curb the rising human and economic costs associated with diabetes. Attaining and maintaining a healthy weight and being physically active are the cornerstone interventions for both diabetes prevention and optimal management. The current overweight and obesity epidemic must be tackled, particularly in children, youth and young adult populations. Canadians must also become more active. Physical activity not only helps individuals manage weight, but it also independently increases sensitivity to insulin. An important national childhood obesity initiative is currently underway. This collaborative approach, agreed to by the Federal, Provincial, and Territorial Ministers of Health, is seeking to make childhood obesity a national priority through the implementation of Curbing Childhood Obesity: A Federal, Provincial and Territorial Framework for Action to Promote Healthy Weights.

Although the care and management of individuals with diabetes has improved in the last decade, there is still room for further improvement. Appropriate glycemic control along with increased screening and more aggressive treatment of complications and risk factors for cardiovascular disease (such as hypertension, hyperlipidemia, and tobacco smoking) require ongoing attention.

Although very important, individual-level interventions will not be sufficient for success. The adoption of healthier lifestyles is complex and is influenced by larger socio-economic factors. For example, heavy marketing of unhealthy food and beverage choices and car-driven urban design are both recognized as having important influences on the current eating and physical activity patterns of the population. Public policies promoting healthy foods and environments conducive to physical activity must be put into practice.

Furthermore, as shown in this report, diabetes is not distributed equally accross Canada. A geographical distribution of diabetes in Canada has shown higher rates in the east, particularly in Newfoundland and Labrador, Nova Scotia, and Ontario, and lower rates in the west and north, particularly in Alberta and Nunavut. After adjusting for age, First Nations populations are particularly affected, with rates two to three times higher than the rest of the population. Similarly, immigrants of non-European descent are experiencing higher prevalence rates. Finally, two other populations require special attention: children and youth, and females of childbearing age. The rising overweight and obesity rates in children and youth as well as the increasing rates of diabetes are particularly worrisome since the early onset of the disease means an increased risk of related complications and lifelong consequences. In addition, besides the well-known short-term impacts of gestational diabetes on the mother and the foetus, it has also been shown to increase the risk of overweight, obesity and diabetes in the child later in life. Although important national initiatives such as the Aboriginal Diabetes Initiative and the Federal/Provincial/Territorial framework on Curbing Childhood Obesity already exist, efforts targeting these populations should continue.

In conclusion, this report highlights some positive news, such as the relatively stable incidence rate over the last decade and the improved longevity of those with diabetes. However, it also demonstrates the important increase in the number of people living with diabetes and the associated impact on the health system. The report also highlights the major effect of obesity in the development of diabetes in younger adults, which may usher in a new wave of diabetes in Canada.